This invention relates to a kit to raise the front end of a vehicle and more particularly to a kit and a method for raising the front chassis of a truck or sport utility vehicle (SUV) equipped with independent front wheel suspension and standard rear wheel drive.
In past years, a number of products have been produced and sold on the aftermarket for light trucks and SUVs which products are designed to raise the front chassis a few inches to enhance the look of the vehicle, i.e. vehicle aesthetics, as well as to accommodate a larger tire than the stock tires that would be supplied by the manufacturer. Heretofore, methods generally used for obtaining greater clearance between a tire and the wheel opening have oftentimes simply installed coil springs of greater length or different spring character that would raise the chassis without making any complementary changes to the suspension; however, it is felt that such adjustments can compromise the original factory design pertinent to suspension movement, wheel alignment and steering geometry, which can very likely result in excessive tie rod angle, excessive ball joint angle and excess A-frame angle all of which lead to excessive tire wear, particularly during cornering. In a few instances, the accommodation of such larger coil springs has been facilitated by removal and relocation of factory pivot points in order to simulate factory wheel alignment specifications at a static height. However, one ensuing problem that often occurs from such a relocation is a tilting outward of the tire, i.e. excessive positive camber; this eliminates a complete contact patch of the tire on the surface of the road and is considered to be extremely dangerous during conditions of severe weather, i.e. snow, ice, rain and/or mud. Moreover, vehicles having such modifications often encounter resulting failure of suspension components during normal vehicle operation, examples of which include cracking or fracturing of an upper A-frame control arm as a result of topping out on a suspension stop, and premature failure of ball joints, tie rod ends, pitman arms and/or idle arms.
In view of the foregoing, it has been felt that new approaches are needed to effectively and safely raise the front end of a vehicle. Particularly sought are arrangements which do not disturb the normal functioning of the front suspension and which do not significantly detract from the ride of the vehicle following such adjustments.
The present invention provides a kit for raising the static height of the front end of a vehicle having independent front wheel suspension which utilizes a spindle supported by upper and lower control arms, generally of the A-frame variety, while substantially retaining the factory suspension geometry of the front wheels and tires. The kit includes a-pair of bracket adaptors for each front wheel, which interfit with the factory brackets and allow an upper-replacement control arm to be attached to the vehicle chassis via mounting holes that are located at least about one inch lower and at least about one inch outboard of the original factory location for such mounting holes. A modified upper control arm having a length shorter than that of the factory control arm carries fittings that interfit with the aforementioned bracket adaptors so as to allow the upper control arm to pivot about a generally horizontal axis. The outboard end of the control arm is essentially the same as the factory control arm; it facilitates normal attachment through a ball joint to the spindle plate to which the front wheel is mounted. Overall, the kit allows the chassis of a light pick-up truck or SUV to be raised at least about 3 inches above factory standard height without subjecting the associated wheel and tire to excessive positive camber when cycling to absorb dips in the roadway.
Overall, there is provided a method for raising the static height of the front end of a vehicle having independent front wheel suspension with minimum disturbance of normal suspension geometry and without change to the factory ball joints, the result of which is an arrangement which permits full normal suspension travel.